1. Field of the Invention
Analyte sensor systems (e.g. glucose sensor systems used in the management of diabetes) and methods and materials for making and using such sensor systems.
2. Description of Related Art
Analyte sensors such as biosensors include devices that use biological elements to convert a chemical analyte in a matrix into a detectable signal. There are many types of biosensors used for a wide variety of analytes. The most studied type of biosensor is the amperometric glucose sensor, which is crucial to the successful glucose level control for diabetes.
A typical glucose sensor works according to the following chemical reactions:
The glucose oxidase is used to catalyze the reaction between glucose and oxygen to yield gluconic acid and hydrogen peroxide (equation 1). The H2O2 reacts electrochemically as shown in equation 2, and the current can be measured by a potentiostat. These reactions, which occur in a variety of oxidoreductases known in the art, are used in a number of sensor designs.
When a sensor such as a glucose sensor is implanted in a patient, started up and then used to monitor glucose, the glucose sensor may not operate continuously in a stable state. For example, the electrical readings from the sensor, which optimally are directly correlated to the glucose level of the patient, can nonetheless vary and are subject to factors which confound sensor readings, for example erroneous reading that can result from phenomena such as suboptimal sensor hydration, sensor noise, sensor drift and the like. In view of such issues, materials and methods designed to further the reliability of sensor readings are desirable.